1. Field of the Invention
The present invention relates in general to an image layout method, and more particularly, to a layout method image quality.
2. Description of the Related Art
The earliest dynamic image visible to human beings was the documentary movie. With the invention of the cathode ray tube (CRT), commercial television has become a necessary home appliance. The development of science and technology has further extended the application of the cathode ray tube into the desktop monitor of the computer industry for the last several decades. However, as various kinds of cathode ray tubes suffer from radiation problems, and the internal electron gun occupies such a large volume, the cathode ray tube has become inapplicable for thin and light products.
The above problems thus initiated the development of flat panel display, such as the liquid crystal display (LCD), field emission display (FED), organic light emitting diode (OLED), and plasma display panel (PDP). Among the above displays, the development of the liquid crystal display is most significant. The liquid crystal display possesses the characteristics of thinness, smallness, lightness and applicability of small, medium and large area display, and has been applied to the portable wireless communication and network techniques.
The image layout method is a key feature determining the quality of the image displayed by the liquid crystal display. Referring to FIG. 1, a layout of a liquid crystal display is illustrated. As shown in FIG. 1, the liquid crystal display 10 includes a data line driving circuit 102, a scan line driving circuit 104, data lines 106 and scan lines 108. The intersection of each data line 106 and each scan line 108 constructs a pixel. In FIG. 1, the application specific integrated circuit (ASIC) 14 is connected to the data lines 106 via the image input lines 16 to drive the liquid crystal display 10. Further, the layout method connecting the image input lines 16 with the data lines 106 affects the image quality of the liquid crystal display 10. When the number of the image input lines 16 is increased, the product of the resistance and capacitance (RC) of the wiring layout of the image input lines 16 is crucial, to affecting the driving capacity of the application specific integrated circuit 14. Therefore, the power consumption of the application specific integrated circuit is affected. On the other hand, when the number of the image input lines 16 is increased, the load difference between image input lines 16 is also crucial and will cause a non-uniform image.
FIG. 2 shows a conventional image layout. In FIG. 2, there are n image input lines. The liquid crystal display includes the pixels 202, the control circuits 204, and n data lines in a single section. As shown in FIG. 2, the data lines are sequentially arranged and connected to the image data lines. That is, the first data line is connected to the first image input line, the second data line is connected to the second image input line, and the nth data line is connected to the nth image input line. Alternatively, in FIG. 2, the data lines can be arranged and connected to the image input lines in a reverse sequence. That is, the first data line is connected to the nth image input line, the second data line is connected to the last second image input line, and the nth data line is connected to the first image input line. Further, as shown in FIG. 2, the first image input line has 0 cross overlap, the second image input line has 1 cross overlap, and consequently, the nth image input line has n−1 cross overlaps. Each cross overlap generates an overlap capacitor. The larger the overlap capacitor is, the more difficult it is to drive the application specific integrated circuit. For such a conventional layout, as each image input line has different numbers of cross overlaps, therefore, the application specific integrated device requires a different driving power to drive each image input line.
In another image layout as shown in FIG. 3, there are n image input lines, and the liquid crystal display includes a plurality pixels and a plurality of control circuits. The pixels and control circuits are divided into a first section 304 to an mth (m is a positive integer) section 304. The first section comprises the first pixels 306, the first control circuits 308 and n (n is a positive integer) data lines 310. Similarly, the mth section 304 includes the mth pixels 312 and the mth control circuits 314 and n data lines 316. For a quarter common intermediate format (QCIF), there are m=176 Ã/n for n image input lines.
As shown in FIG. 3, the data lines in each section are connected to the image input lines with a reverse sequence. That is, the nth data line is connected to the first image input line, the (n−1)th data line is connected to the first image input line, and the first data line is connected to the nth data line. In addition, in FIG. 3, the data lines can also be connected to the image input lines sequentially. That is, the first data line is connected to the first image input line, the second data line is connected to the second image input line, and the nth data line is connected to the nth image input line. As shown in FIG. 3, the numbers of cross overlaps of the first, second and third image input lines are 0, 1 Ã and 2 Ã. Consequently the nth image input line has (n−1)Ã m cross overlaps. With such a conventional layout, the number of cross overlaps for each image input line is different, causing different load and overlap capacitance. Therefore, the application specific integrated circuit requires a different driving power to drive each image input line. Further, between two consecutive front and rear sections, the nth data line of the front section is connected to the first image input line, while the first data line of the rear section is connected to the nth image input line. As the number of cross overlaps between the connected data lines and the image input lines varies too much, the images displayed by two neighboring sections contain a gap, seriously affecting the image quality.